2009 by ELTRA GmbH Germany – July 2009 – Service Manual Thermostep
Page 24
An interruption of rotation of caroussel can occur when:
a.)
Crucible caroussel is not lifted up
b.)
an incorrect position or a defective motorsensor
c.)
a defective gear belt
d.)
a defective motor
At a.) Condition for rotation of motor is an elevated crucible caroussel to avoid damaging of
the balance by lowered crucibles.
Check if gas pressure of compressed air is sufficient (nearly 4 bar). At low gas pressure of
compressed air it is not possible to elevate crucible caroussel (see Fig. 2.2).
The same principle is true for an incorrect adjustment of the sensor of crucible caroussel,
because the software does not get proper information of status of caroussel. Check if status of
caroussel is shown correctly at the software (Form –
Controller
:
Inputs
) and correct it if
necessary (see
1.2
).
Check if it is possible to lift up crucible caroussel manually (see Operation manual; Form –
Controller
). If this is not possible, despite sufficent gas pressure of compressed air, the
respective valve (LHS: 4. valve at the valveblock) or the cylinder of caroussel could be
defective (see
3.1
rsp.
3.3
).
At b.) An incorrect adjustment of the motorsensors (see
1.12
) could be reason for this error.
The homesensor is needed for termination of a complete rotation, whereas the movesensor
observes the rotation itself. If one of the sensors not correct reply at the software, the motor
will be stopped to avoid its overheating.
If the home sensor is not able to detect the encoding screw the motor will be stopped after
nearly two full rotations accompanied by an acoustic signal. Is the movesensor not able to
detect the rotation of the gear wheel the motor stops before reaching the next crucible position
accompanied of an accustic signal.
To check the home- or the movesensor open form –
Motor
and
form –
Controller
. Click at
HOME
and look during rotation if both sensors are activated (Form –
Controller
:
Inputs
).
Please note: The homesensor is activated only once at every full rotation (near Position 20)!
If one of the sensors does not reply check its functionality first. Bring a magnetizable item
(e.g. a screwdriver) next to the sensor and check if now an activation of the sensor is able at
the software.
If an activation is possible adjust the sensor position (see
1.12
).
If no activation of the sensor is possible replace the sensor (see
3.15
).
At c.) If the gear belt is defective or loose a rotation of the caroussel is not possible and the
motor is switched off to avoid its overheating.
Check the tension of the gear belt from LHS by moving the caroussel manually with the aid of
the encoding plate. At proper tension of the gear belt the rotation should be smooth with
constant effort. If rotation accompanied with jerky movement the tension of gear belt too
loose and has to be retighten (see
3.10
).
At d.) If it is not possible to solve the problem with a.)-c.) it is possible that the motor is
defective. At this case it is probably necessary to replace the motor (see
3.10
). Please contact
manufacturer.
